(1) Field of the Invention
Exemplary embodiments of the present invention relate to a method of modulating/demodulating a signal, an apparatus for performing the method and a display apparatus including the apparatus. More particularly, exemplary embodiments of the present invention relate to a method of modulating/demodulating a signal that substantially increases bit efficiency by substantially broadening a bandwidth, and an apparatus for performing the method and a display apparatus including the apparatus.
(2) Description of the Related Art
A flat panel display apparatus using liquid crystal or plasma has been developed. More particularly, flat panel display apparatuses, such as liquid crystal display (“LCD”) apparatuses or plasma display apparatuses, for example, using flat panels in products such as cellular phones, computers, televisions (“TVs”), for example, have been developed.
Additionally, LCDs that display images using electrical and optical characteristics of liquid crystal have been developed to have improved resolutions and increased screen sizes.
Generally, an LCD apparatus includes a display panel that displays an image by controlling an amount of light that passes through liquid crystals and a transparent substrate. Additionally, a backlight unit (“BLU”) provides the light to the display panel, and a circuit drives the display panel and the BLU. The circuit includes, for example, a gate driving circuit, a data driving circuit and a timing control circuit.
The display panel typically includes an array substrate, an opposite substrate disposed opposite to, e.g., facing, the array substrate and a liquid crystal layer disposed between the array substrate and the opposite substrate and including the liquid crystals therein. In addition, the array substrate may include a plurality of data lines, a plurality of gate lines and a plurality of pixel electrodes. The display panel typically includes an active area and peripheral area. The active area displays the image and the peripheral area surrounds at least a portion of the active area. The gate driving circuit and the data driving circuit, for example, are disposed in the peripheral area.
The gate driving circuit and the data driving circuit receive control signals from the timing control circuit disposed on the printed circuit board (“PCB”) and thereby drive the display panel. In a conventional display panel, many channels for communication are required between the gate driving circuit and the data driving circuit.
When the required number of the channels is increased, power consumption is substantially increased and electromagnetic interference (“EMI”) is generated.
Accordingly, a method of serially transmitting data signals has been developed in efforts to reduce the EMI and realize high-speed data transmission with low power consumption.
The method of serially transmitting data signals may transmit a clock signal and a data signal at the same time using one transmission line. The method of serially transmitting data signals may include, for example, a pulse width modulation (“PWM”) method, a clock embedding modulation method or a clock edge modulation (“CEM”) method.
In the CEM method, a rising edge of a clock signal is transmitted to restore a clock signal from a transmitting terminal (or a modulator) to a receiving terminal (or a demodulator). However, a position of a falling edge of the clock signal may be changed by a phase-locked loop (“PLL”) circuit in the transmitting terminal (or the modulator), to represent data signals based on the position of the falling edge of the clock signal.
Accordingly, it is desired to develop a method of serially transmitting data signals that substantially increases bit efficiency and/or a bandwidth.